1. Field of the Invention
The present invention relates to a vehicle seat lumbar support system including a compressible plastic support structure which includes an integrally molded spring, and a cable operative to adjust the compressed position of the plastic support structure against a lower seatback cushion for lumbar adjustment.
2. Background Art
For ergonomic and therapeutic reasons, it is desirable to provide adjustable support to the lower lumbar region of a person""s back when seated for long periods of time. As automobile driving often entails long-seated periods with only limited movement, lumbar support mechanisms are a welcome addition to many automobile seat assemblies. The lumbar support mechanisms must be adjustable in view of varying body sizes and shapes of automobile drivers and passengers, as well as the desire to alter one""s seating conditions from time-to-time.
Adjustable lumbar support systems typically provide a mechanism or inflatable device located in the seatback adjacent to the lumbar region of the passenger""s back. This allows the passenger to adjust the extent to which a lumbar support member protrudes from within the seatback. As a passenger begins to experience fatigue, adjusting the position of the lumbar support member can reduce fatigue and increase customer satisfaction.
The prior art has advanced many types of adjustable lumbar support mechanisms for the automobile seat environment, including both manually adjusted and power adjusted units. A wide variety of such systems are available. These systems often suffer from one or more problems, such as complexity of construction and consequent expense. Less complicated and less expensive systems may be less effective in operation.
While nearly all prior art lumbar support mechanisms function satisfactorily, there remains the ever-present desire to further reduce both cost and weight, while maintaining and/or increasing durability, functionality, and assembly.
The present invention provides a vehicle seat lumbar support adjustment device which includes a compressible plastic support structure with an integrally molded spring.
More specifically, the present invention provides a vehicle seat lumbar support adjustment device including an actuator operatively connected to a cable which extends across a seatback. A compressible plastic support structure is positioned between the cable and a cushion layer, and movable toward the cushion layer by tensioning of the cable in order to adjust lumbar support for a seat occupant. Preferably, the compressible plastic support structure includes an integrally molded spring component positioned between opposing walls of the support structure.
The integrally molded spring component is formed by intersecting walls of the support structure. The intersecting walls cross over each other to form at least one generally X-shaped configuration when viewed in horizontal cross-section.
Another aspect of the invention provides a vehicle seat occupant protection system including a compressible plastic support structure positioned behind a cushion layer in a seatback. The plastic support structure includes an integrally molded spring component positioned between opposing walls of the support structure. The plastic support structure is sufficiently compressible to provide a catcher""s mitt-type occupant protection system at low vehicle speeds wherein, upon rear impact, the occupant penetrates deeply into the seatback by compressing the plastic support structure during impact so that the occupant is retained in the seated position.
Accordingly, an object of the invention is to provide a vehicle seat lumbar support adjustment device including a flexible, compressible plastic support structure which is adjustably compressed against a cushion layer by an actuator-adjusted cable extending across the seatback.
Another object of the invention is to provide a lumbar support adjustment device in which cost and weight are reduced while maintaining and/or increasing durability, functionality and assembly.
The above objects and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.